In times past you could order a suitable crystal from International Crystals in Oklahoma. 
Unfortunately, due to the proliferation of frequency synthesizers, they are no longer in business. 
There was another provider of custom crystals in Ft Myers Florida but they are out of business 
for the same reason. I have ordered custom crystals from both of these manufacturers several 

Another way to generate the exact frequency, for experiential purposes, is you could purchase 
one of several relatively cheap units to generate the desired frequency. 
Circuit boards using the ASF4351 synthesizer chip are available on E-Bay for about $40.00. 
Unfortunately, these require an external programmer to set up. 
A complete unit with programmer included is about $150.00. 

Hopefully, this will be a good starting point for you. 

-----Original Message-----
From: JoAnne Maenpaa <>
Sent: Sun, Nov 6, 2022 3:28 pm
Subject: [AMSAT-BB] Re: Crystals for 2m

Quite a few crystal oscillators in a receiver are running on the third-harmonic of the crystal's fundamental frequency. The local oscillator in consumer scanning receivers was calculated with this formula:
  • Receive frequency - 10.7 MHz / 3 = crystal frequency

The formula generated a local oscillator frequency that was the first IF frequency (10.7 MHz) after the mixer stage.

On 11/6/2022 12:33 PM, Andy Brian wrote:

I'm looking for good source of crystals between 156.5 and 156.600MHz for build experimental
linear transponder. Please for any got information or some other solutions.
I received a few from marine scanners but it seems not 156Mhz

73 de JoAnne K9JKM
BM DMR TG 98006


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